Its about the economy, not the strength. The CC of ROM and UKR cannot be replaced by alien crews (no matter the passport) as the salary lever does not allow relocation or commute from other countries, and there is no cheaper foreign workforce available. That gives them a small piece of wood to stand on and hold their ground.
Neither of which would apply to pilots who are mobile and thus replaceable from the outside. You want the EEs to have a union? Don't come to fill their seats after they got fired for starting one, ffsk!
Yes, adding the list, the Hungarian Union has also failed to materialize many times (well before your average PPRuNers time) as did the Polish one of RYR pilots in 2018.
Speaking of RYR holdings, how well did the union go for the Austrians from Lauda motion who had their CBA signed and published on the ministry's website, all legal and proper? A.K.A it does not get any more west than Ireland in the EU, it does not get any more cultural than Vienna in the EU, it does not get any more pilot-unionized than the US shareholders. Still meant nothing.
There is some good progress recently. Tracking back to RYRs return to France, full employment contracts in Spain and Italy, fire still burning strong for the good cause in Denmark and Netherlands. Wizz losing the plot in Scandinavia.
The difference is not about individuals being less or more chicken****, it's whether or not you can replace the pool. Reagan / ATC is mandatory reading ND 49er's too.
If it is too large or too costly to replace, after years of causing grief and building all imaginable obstructions, the Corporation will tolerate the existence. If there is no other cheaper way.
The small countries and tiny bases of EE lack the leverage of causing economic loss to the company.